The art market roared back to life during its annual trip to Miami Beach, with galleries reporting double-digit sales growth at Art Basel's winter show. Bouncing back from last year's weak showing, nearly 75 percent of galleries at Art Basel Miami Beach said sales revenue grew at least 15 percent over 2008. More than a third reported a sales hike of more than 30 percent. ``Everybody's happy this year,'' Rachel Adler, owner of Adler & Conkright Fine Art in New York, said Sunday.